1. Field of the Invention
The present invention relates to corrosion-resistant copper materials which undergo substantially no surface corrosion or oxidative deterioration due to heat or aging, and to a method for the production of the same.
2. Prior Art
Because copper materials are soft, relatively stable metals, they are often used in roofing such as for Shinto shrines and Buddhist temples, and in decorative art, for example. In addition, their high thermal conductivity and electrical conductivity, second only to those of silver, make them indispensable today as metal materials in electrical applications, such as electrical wires and leadframes for semiconductor devices. However, because the copper materials are more reactive than gold and silver, they are readily oxidized and subject to surface corrosion due to heat and aging. For use in automotive and electrical applications requiring heat resistance, they are generally plated with nickel, palladium or the like. But plating with nickel or the like results in a loss in the distinctive reddish tone of copper, and also makes the surface more difficult to work with.